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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        var arr = [
            {name:"html",value:"12px"},
            {name:"css",value:"13px"},
            {name:"vue",value:"11px"}
        ]
        arr.map(item =>{
            var result = parseInt(item["value"])*2
            return item["value"] = result
        })
        console.log(arr);
        
        var res = []
        for(var key in arr){
            arr[key].value = parseInt(arr[key].value)*2;
            res.push(arr[key])
        }
        console.log(res);
    </script>
</body>
</html>